astro-ph.IM – My WordPress Site

Schematic overview of the data-processing workflow in this work. After splitting the 2C data into three antenna spectra, we first conduct a general comb diagnostics for each antenna, then perform per-antenna PCA decomposition, basis alignment, and periodogram/FT/ACF analysis. The component-level results are finally combined to distinguish non-shared periodic signals from shared or comb-like RFI. -- astro-ph.IM

Artemis & Lunar Exploration, Astronomy & Telescopes, Biosignatures & Paleobiology, Missions & Hardware, Moon, SETI & Technosignatures

First Lunar Farside SETI Observations for Periodic Signals With The Low-frequency Radio Spectrometer Of Chang’E-4 Mission

by Keith CowingApril 12, 2026April 12, 2026

Chang’E-4 (CE4), the first mission to soft-land on the lunar farside, provides a unique opportunity for astronomical observations from an environment shielded from terrestrial radio interference, and thus serves as pathfinder for lunar farside radio search for extraterrestrial intelligence (SETI) studies.

Detrended QLP light curves

Astronomy & Telescopes, Biosignatures & Paleobiology, Intelligence & Language, SETI & Technosignatures

A TESS Test of the Hybrid Ring Strategy for Technosignature Searches Using GRB 221009A

by Keith CowingApril 9, 2026April 9, 2026

Sky plot of nine cPIC targets that are present in all stellar reference samples. Their PIC names are indicated with labels. -- astro-ph.IM

Astronomy & Telescopes, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Missions & Hardware

Planet Finder PLATO Input Catalogs For Technical Calibration And Fine Guidance

by Keith CowingApril 6, 2026April 6, 2026

Artist’s impression showing possible choices for the scale of human involvement in the future of Mars.

Atmospheres, Climate, Weather, Beta Pictoris, Biosignatures & Paleobiology, Desert Worlds, Gaia - Planetary Perspectives, Mars, Terraforming & Geoengineering, Water/Hycean Worlds & Oceanography

A Research Roadmap For Assessing The Feasibility Of Warming Mars

by Keith CowingApril 3, 2026April 3, 2026

Four diagnostics of electron bombardment on Europa’s leading hemisphere: (a) total deposited-energy flux, (b) deposited-energy fraction, (c) mean secondary-electron energy, and (d) e-folding (≈ 63%) deposition depth. Cells with no electron flux in the relevant energy range are shown in gray. -- astro-ph.IM

Astrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Interstellar

Geant4-IcyMoons: Simulating Electron Interaction Physics in Irradiated Astrophysical Ices

by Keith CowingApril 3, 2026April 3, 2026

A region in Ursa Major with maps of individual simulation components and their sum; these have been evaluated for a spectral channel centered on 0.803 µm. The color schemes vary in order to best illustrate the features of the individual signals. Notice how the scan pattern manifests in several of the components. The contributing images were generated with the Sky Simulator described in B. P. Crill et al. (2025). Real flag masks (Sec. 3.2) have been applied and are most noticeable at the centers of bright stars. -- astro-ph.IM

Astrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Imaging & Spectroscopy, Interstellar, Missions & Hardware

Spectral Map Making With SPHEREx

by Keith CowingMarch 30, 2026March 30, 2026

Overview of the 3 m Lazuli Space Observatory and its three instruments, the Widefield Context Camera (WCC), the Integral Field Spectrograph (IFS), and the ExtraSolar Coronagraph (ESC). Main properties and characteristics of the telescope and the instruments are highlighted. -- astro-ph.IM

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Citizen Science / Open Science, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Missions & Hardware, Stellar Cartography

The Lazuli Space Observatory: Architecture & Capabilities

by Keith CowingMarch 26, 2026March 26, 2026

Scatter plots of potential candidate in frequency, drift rate and signal-to-noise ratio for each polarization channel. The color and the size for each point represent the value of SNR in log space. The green and red color bar is the frequency ranges of civil aviation and navigation satellites, respectively. The black dashed lines represent the expected drift rates for each observation date. -- astro-ph.IM

Astronomy & Telescopes, Biosignatures & Paleobiology, Comets and Asteroids, Intelligence & Language, Interstellar, Magnetic Fields, Electromagnetism, bioelectricity,, SETI & Technosignatures

Narrowband Radio Technosignature Search Toward 3I/ATLAS With FAST

by Keith CowingMarch 21, 2026March 21, 2026

The strength of indirect detection signals from an Earth-like exoplanet as a function of stellar effective temperature. Bands encompassing main sequence spectral classes A through M color coded by temperature are indicated at the top. Here, Earth-like is defined as a 1-Earth mass object in an orbit receiving irradiance equivalent to 1 AU from our Sun (the solar constant). Radial Velocity signals (solid blue line) are seen to exhibit a rapid rise in signal strength (given on the right-hand abscissa) for cooler, M dwarf systems where they become detectable with present submeter per second RV precision. On the other hand, astrometric deflection signals (colored diamond symbols) rise with host star temperature, and decline linearly with distance from values of up to several microarcseconds for the nearest stars. For convenience the plot also indicates the size of the temperate orbit modeled (in AU, left abscissa) and its corresponding orbital period (in years, also left abscissa). -- astro-ph.IM

Alpha Centauri, Astronomy & Telescopes, Biosignatures & Paleobiology, Cubesats and smallsats, Habitable Zones, Imaging & Spectroscopy, Missions & Hardware

The TOLIMAN Mission: A Low-cost Space Telescope For High Precision Narrow-angle Astrometry

by Keith CowingMarch 18, 2026March 18, 2026

The astrometric and RV signals of Earth analogs orbiting nearby stars are small and below the current state of the art, while the astrometric signals of such planets are positively correlated with their angular separation but anti- correlated with their contrast and RV signal. (left) The amplitude of the astrometric reflex signal versus the radial velocity reflex signal for Earth-mass planets receiving an Earth-like instellation orbiting a sample of nearby stars that are likely to be targets for HWO direct imaging. Credit: Eric Mamajek, used with permission. (right) Contrast versus astrometric signal for a similar sample of stars hosting Earth-like planets. The size of the circles are proportional to the angular separation of the planet and the colors of the circles are proportional to the RV amplitude. -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Gaia Mission, Imaging & Spectroscopy

Masses of Potentially Habitable Planets Characterized by the Habitable Worlds Observatory

by Keith CowingMarch 16, 2026March 16, 2026